Irrational: meaning, definitions and examples

Use when someone is acting based on emotions rather than reason or logic.

• His fear of spiders is completely irrational
• She made an irrational decision to quit her job without a backup plan

Use when something does not follow a sensible pattern or reasoning.

• His argument was illogical and didn't make sense
• The plan was illogical and bound to fail

Use when someone is not willing to listen or compromise, often in a way that's seen as unfair.

• Her demands were unreasonable and couldn't be met
• It's unreasonable to expect me to finish all this work in one day

This word is often used to describe thoughts, actions, or emotions that do not make sense or cannot be explained by reason. It can be used in everyday conversation to describe behavior that lacks logical reasoning.

• His fear of spiders is completely irrational.
• It was irrational of her to quit her job without having another one lined up.

Similar to 'irrational', 'non-rational' is used to describe actions or thoughts that are not based on reason or logical thinking. It is often used in academic or formal discussions.

• Believing in superstitions is a non-rational behavior.
• The decision seemed non-rational given the available evidence.

This word is commonly used in everyday language to describe demands, expectations, or behaviors that are not fair or sensible. It often carries a negative connotation.

• It is unreasonable to expect a perfect score without studying.
• Her demands were completely unreasonable.

This term is less common and typically used in more technical or philosophical discussions where an emphasis is placed on the formal aspects of logic. It may also appear in academic writing.

• The process was random and non-logical by nature.
• His theory included several non-logical jumps.